DE1176335B - Method and device for regenerating a moisture exchanger for air conditioning systems - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Boarding school Kl .: F24f

Number:
File number:
Registration date:
Display day:

German KL: 36 d- 1/58

1176 335
M 37310 X / 36 d
April 11, 1958
20th August 1964

The invention relates to a method and an apparatus in use in a moisture exchanger for air conditioning systems with a transfer body is provided, to which an air stream in it gives off steam, while a regeneration stream absorbs this vapor from the transfer body at another point. The moisture exchanger is provided with a housing, which has inlets and outlets for the air flows. The housing and the transmission body ι ο perform a relative movement to each other in a closed path, while the two air flows are passed through the transmission body at separate points. The transfer body is made up of a mass that forms continuous channels and that of a mass that adsorbs or absorbs the vapor Consist of or contain such a substance. In the following description the most important Field of application of the invention treated, wherein an air stream containing water vapor in the Moisture exchanger is dehumidified and the active mass of the transfer body is hygroscopic Possesses properties.

It is known to design moisture exchangers with a stationary housing in which the transmission body moves on a closed path, the various parts of the transmission body during a cycle alternately on the one hand from the one to be dried or to be dehumidified Air flow, also called primary air or primary flow, and on the other hand from a regeneration air flow, The relative moisture content must therefore be low enough to avoid that of the transfer body to be able to drive out absorbed moisture. At a known design, the transmission body has the shape of a rotor or wheel. The low one relative moisture content, which the regeneration air flow must have, can in the simplest way can be achieved in that a heating device in its supply line to the moisture exchanger is arranged. During the passage through the transfer body, the moisture content increases of the regeneration stream, and at the same time its temperature falls. Nevertheless, the regeneration stream has practically always a considerable excess temperature or an unused one when leaving the apparatus Heat content. The regeneration flow must therefore be given an excess of heat, the heat-economical Limit of the moisture exchanger sets.

Method and device for regeneration
a moisture exchanger for air conditioning systems

Applicant:

Carl Munters & Co., Stocksund (Sweden)

Representative:

Dipl.-Ing. E. Jourdan, patent attorney,

Frankfurt / M., Frhr.-vom-Stein-Str. 18th

Named as inventor:

Carl Georg Munters, Stocksund,

Per Gunnar Norbäck, Lidingö (Sweden)

Claimed priority:

Sweden April 12, 1957 (3570)

When the moisture exchanger becomes an apparatus or system for air conditioning a room should have a lower temperature and lower humidity than the outside air this air during the dehumidification process has as little temperature rise as possible above that also find out which is caused by the dehumidification itself and which in temperature and humidity diagrams is represented by the enthalpy lines. Better known for moisture exchangers Art is therefore the transfer of sensible heat from the transfer body to the primary air kept low that the transferred mass of the transmission body in the unit of time between the two air flows is chosen as small as possible.

In order to further reduce the undesired addition of heat to the dried primary air, has also already been proposed, between the regeneration and drying zones of the moisture exchanger to provide a small sector through which untreated primary air is flushed, whereby the transfer body is cooled before it enters the last-mentioned zone during circulation will. The small air flow required for cooling is then introduced into the regeneration air flow, so that the heat it absorbs benefits regeneration. These measures are indeed suitable for improving the moisture exchanger in terms of thermal economy, but

409 657/119

there is also the disadvantage that the escaping regeneration air flow, as from the above statements shows, has a large unused heat content.

The invention aims to improve the efficiency of a moisture exchanger, i.e. H. The relation between the heat of steam formation of the removed amount of water and the amount to be sacrificed for this Amount of heat to improve. This is essentially achieved by a method according to the invention achieved in that the heat supply required for the regeneration to the mass of the transfer body either wholly or partially through one through the channels of the transmission body guided gas flow, for example air flow, takes place in a circuit between the mass and a Heating device is circulated. According to another characterizing the method according to the invention The heat is supplied either in whole or in part by a steam-rich feature Air flow that occurs both before and after passing through the mass of the transmission body has higher, and preferably a significantly higher, steam content than the primary stream. Here, the circulation circuit is set to a water vapor content that is both before and after the passage through the mass is higher, and preferably is substantially higher than the water vapor content of the primary current and the surrounding atmosphere. It is essential for the invention that at most a small amount of air is sacrificed to carry out the regeneration, so that as a result, the drainage loss is very small. With climatic treatment of air, the regeneration perform the mass of the transmission body with an amount of air that z. B. only 5% of the Primary current is.

The invention is explained with reference to some exemplary embodiments shown in the drawing for carrying out the method is described in more detail, and there are others, the invention identifying features indicated.

1, 3, 5 and 7 show, in a schematic diagram, four exemplary embodiments for a moisture exchanger, parts of the apparatus housing being cut away for the purpose of better clarity.

FIGS. 2, 4, 6 and 8 illustrate diagrams for temperature and moisture content associated with the exemplary embodiments in question, which are called "tx diagrams" in the following.

In the various figures, the same reference symbols are used for the same or equivalent parts used.

In the exemplary embodiment according to FIG. 1, denoted by the associated t-x diagram according to FIG. 2 10 a cylindrical housing in which a transmission body 12 designed as a rotor is mounted on a shaft 14 is stored. The transmission body contains a mass with hygroscopic properties, which are preferably composed of a carrier and a hygroscopic material attached to it is. The carrier has a large number of channels running through the rotor in the axial direction. The crowd of the rotor is designed in one way or another so that free passages in the axial direction are present while the means flowing through these passages are prevented from while flow their way through the rotor in the peripheral direction. In the embodiment shown the mass of the transfer body consists of sheets or foils, each of which is preferably second sheet 16 is flat and every second sheet 18 is corrugated, so that continuous axial channels are formed, which are separated from each other in the lateral direction. The sheets or foils are made expediently made of paper, e.g. B. Asbestos paper, which is the eligible, relatively high Can withstand temperatures and with a moisture adsorbent such as lithium bromide or chloride, is impregnated. The distance between the flat sheets 16 is in order to achieve a high exchange per volume unit and thus achieving a good degree of efficiency is expedient as small as possible, expediently less than 3 mm, and preferably to 2 mm or slightly less, held.

The housing 10 is below the rotor 12 by two radially extending partition walls 20 and 22 in FIG two sectors or chambers 19 and 21 divided. There are partitions in the housing above the rotor 24 and 26 arranged, which are aligned with the aforementioned walls. There is also a third Intermediate wall 28 is provided so that the upper housing part in three separate sectors or chambers 32, 34, 40 is divided. The primary air from the room whose air is being dehumidified is to be fed by a fan 30 to the sector 19 located at the bottom left in FIG. 1. The air passes through the channels of the rotor and then flows partly to that of the housing and the Partition walls 26 and 28 bounded sector 32 and partly to that of the housing and the Sector 34 delimited by partition walls 24 and 28. Sector 34 extends over a substantial part smaller angle than sector 32. The flow paths are through those ending with arrowheads Double lines shown. The flow path 36 denotes the air flow through the larger Sector 32 goes and which, after being dehumidified, is to be used to renew the room air. Of the Flow path 38 embodies an auxiliary air flow, which has the task of the rotor body, as later in individual explains how to dehumidify and cool.

In the sector 40 delimited by the housing 10 and the partition walls 24 and 26 flows in Air flow through the channels of the rotor body 12 in the direction of the indicated by the arrow Flow path 42. This flow leaves the rotor body at sector 21 and is then through a Fan 44 through a heating device 46 and from there along the flow path 48 to the sector 40 returned. The pipe connections to the housing carried out in a known manner and required and outside of it are omitted for the sake of clarity.

In the associated t-x diagram in FIG. 2, the ordinate embodies the absolute steam content of the Air, e.g. B. in g / kg air, and the abscissa the temperature of the air. Some curves are shown which represent the various relative humidity values of the air. The one introduced by the fan 30 Primary air has the state at point 50, which has a value of about 60% relative humidity and Corresponds to a temperature of 25 ° C. In the apparatus, this air is set to the state at point 52

5 6

dried, which has a value of z. B. take 5% relative, and has on their exit from the rotor

Represents humidity and 50 ° C temperature. Which they drove out of this the amount of moisture,

Difference between the distance between these points as the rotor moves along the sector

on the line 66 from the abscissa represents the moisture 32 was fed past. The auxiliary air receives one

amount that has been removed from the air. 5 final state with a moisture content that by

During the absorption of moisture in the part, the ratio between the size of the air currents the mass of the rotor body, which is determined between those in the flow path 36 and 38. if Sectors 19 and 32 are located, the mass is more so the air flow in flow path 38 is about 5% and more enriched with moisture and must make up the flow of air in flow path 36 and therefore be regenerated. For this purpose, the latter runs 8 g / kg to the rotor, the increases the rotor 12 slowly rotates, e.g. B. with some um- moisture content of the air flow in the flow revolutions per hour, namely in the through the weg38 to 160 g / kg. In Fig. 2 this is Arrow 54 in FIG. 1 direction indicated, and the moisture content by the dash-dotted line part of the mass enriched with moisture reaches 64 indicated. The temperature of this air stream between sectors 21 and 40 and each being 15 is lower than that at point 60. It is useful by the inherently closed flow path 42, the absolute moisture content of the air flow in the 48 circulating air stream heated. At the outflow path 38 in, an order of magnitude of management example according to Fig. 1 and 2 is assumed to be about 5 to 50 times that of the climate this air flow is for the most part kept from animal air.

There is water vapor. In the diagram F i g. 2 let 20 If the mass of the rotor is taken in the sector 32, that the change of state occurs, it is regenerated and is capable of the air flow Vapor-rich atmosphere of the parallel to the abscissa in the flow path 36 along the line 66 of FIG. 2 Follow len line 56. to dry at point 52. At the same time is the

The line 56 is actually further up in the mass through the auxiliary air in the flow path 38 geDiagram; However, for reasons of space it has been cooled to a lower level.

placed. So the diagram lies neither with this. The advantage of being in a closed circle

even in the other examples, a uniform, circulated, steam-rich atmosphere is one-

Based on the scale. on the other hand, that after the passage of the rotor

In front of the heater 46, the amount of heat remaining in the air stream, rich in steam, is constant Atmosphere the state in point 58, it leaves the 30 is fed back to the rotor and not how Heater then in the state at point 60th is lost so far. On the other hand is the temperature The circulating steam-rich atmosphere flows, the mass sufficiently high, so that only a very after being heated to the state at point 60, a small part of that has been introduced by fan 30 is, through the channels in the rotor 12 and first primary air needs to be sacrificed to the in turn warms its mass. The steam-rich 35 evaporation or boiling off of the mass The atmosphere is thereby cooled, and as it is produced by adsorbed or absorbed vapor. the does not suggest that an intake of auxiliary air in the flow path 38 leaves the apparatus Moisture takes place, changing the atmosphere with a temperature that is opposite to ordinary their state along the same line 56 but may be significantly higher in systems; The other way around Direction. When leaving the rotor 4 ° attention is paid to the one lost in this way it has again assumed the state at point 58- amount of heat because of the small volume of the men. The state at point 58 corresponds to an air flow in flow path 38 which is much smaller Temperature of over 100 ° C, e.g. B. 120 ° C, and than the conventional systems. This works a relative moisture content of e.g. B. 30%. focus on the economics of drying, which The data in point 60 can then be very favorable with 220 ° C 45 according to the invention, and accept 2.5%. The mass of the rotor body should instead be the small amount of air that is off thus do not yet worry about any moisture drift of moisture alone, d. H. without freed, but to a temperature immediately with the help of the preheated steam-rich atmosphere, that of point 60 has been heated. the air flow would have to be heated to a temperature

If the mass becomes 50 during the further rotation, which is practically impossible to work with,

of the rotor comes into the narrow sector 34, if it is assumed that the temperature of the

it is circulated between the steam-rich atmosphere by the auxiliary air in the flow path 38

that changes the initial state according to point 50 120 ⁰ C (point 58) and 220 ° C (point 60)

in the diagram of FIG. Due to the previous and the circulated amount five to ten times larger

When heated, the mass has as much heat as the amount of air flow in the flow path

taken that this is sufficient to that of the 38, based on the unit of time, it follows that

Mass adsorbed moisture in the auxiliary air flow, the small air flow in flow path 38 still

to drift. In order to regenerate the mass of the rotor would have to be heated proportionally higher, i. H.

To be able to do this, the auxiliary air in the flow path needs temperatures that exceed 500 to 1000 ° C

38 only a few percent of what would be ^{6 ° from fan 30,}

to make out the guided primary air. The embodiment according to FIGS. 3 and 4

Due to the heat that is in the mass of the rotor differs from that described above has been stored, the auxiliary air is heated and thus essentially by the fact that in the im through the brought to a relative moisture content, the flow path 42, 48 formed a circuit around the Air flow allows air to continuously evaporate by creating a circulating, vaporous atmosphere Moisture from the mass is supplied, while a corresponding part of the to take. The auxiliary air will therefore escape into the environment both at the Tem- mixture. In this case temperature as in the absorbed moisture content is the small auxiliary air flow that does the job

examples of the pressure conditions in the various Parts of the apparatus must be adjusted so that the intended flow patterns occur. Furthermore, it applies to all exemplary embodiments that any leakage of air is always in the direction to the other sector or sectors away from the sector that is to be taken from the primary air flow is crossed out, and a reverse leakage path must not arise. Therefore, in the latter

Has. To remove moisture or cold from the preheated mass, from already dehumidified primary air; however, it can also consist of untreated air, as in the example according to FIG. 1 and 2 is the case, just as conversely in the latter case the auxiliary air flow consists of dehumidified primary air can.

The two radial partitions 22 and 26
cursed again. An intermediate wall 68 is provided in the housing below the rotor, the absolute pressure of which in the sector is higher than in all of the sectors in front of the other sectors together with the intermediate wall 22. The importance of this operating handenen housing space in two sectors 19 and 21 condition can be seen when z. B. divides the sector 40, these sectors can be the same size of Fig. 3 is considered, where the rotor through or also the sector 19 is larger than the sector 21 has an addition of a few percent auxiliary above the rotor Partition 24 which is air-dried. If only a few of the same position as in the above-described percent of the steam-rich atmosphere were out of play, while the partition 28 was omitted from the sector allocated to this atmosphere, so that in this case the sector 32 would leak in for the primary air flow, the dry would extend over a larger angle. The primary air introduced by the ventilator 30, which is more or less questioned, will become so.

the same way as before between the points SO In the example described, the

and 52 in the diagram of FIG. 4 dehumidified. In the small auxiliary flow in flow path 72 not for sector 32, flow path 36 splits so as to provide for removal of the entire amount of steam which is part of flow path 70 intended to be expelled from the rotor and follows air conditioning while a small one Auxiliary air 25 auxiliary air flow is therefore before its mixing in flow in flow path 72 through the mass of the circulation circuit (flow path 42, 48) on a rotor over a sector, the angle of which by the
Partitions 24 and 68 are determined, vice versa.
As before, the auxiliary air flow only consists of
a small part, about 2 to 15%, of the entire 30
Primary air volume.

The auxiliary air flow in the flow path 72 is expediently circulated in front of the heating element 46 mixed in a vapor-rich atmosphere. It

it is assumed that the mixture is in the state in which the rotor is guided. In this case, the small point 74 of FIG. 4 has and through the radiator auxiliary air flow of the outside air with the help of a valve is taken along the horizontal line 76 to the state in the lators 86 and then heated in a sector point 78. The line lies upwards in the diagram that is lower than the line 56 in FIG. The air stream flows through the rotor along a uniformly defined scale. The vapor flowing in the flow path 38 and enters a sector, flow path 42 to the rotor, which consists to a very large extent through the intermediate walls 24 and 28 in the upper rich mixture, part of the apparatus housing is limited. From here, about 30 percent of the space is made of steam. However, it has the result that it is located outside the housing 10, mixing of air into the steam-rich atmosphere 45 through the flow path 90 in the result that this not only in the sector 40 limited by the partition walls 88 and 92 mass of the rotor to heat, but also fed back the moisture sector on the underside of the housing, able to absorb activity from it. However, the air flow then again flows through the amount of auxiliary air flow in the flow path 72 rotor and escapes via an upper sector, which is small but because the mixture has a high temperature 5 ° between walls 24 and 94, the moisture absorption capacity is the The atmosphere. Instead, it can be very large even in a small amount of air. The change of state
the steam-rich atmosphere follows during the
Passage through the mass of the rotor approximately
the line 80 of FIG. 4. The moisture content of the 55th
steam-rich atmosphere rises, and the line 80
forms an angle with respect to line 76. Of the
End condition at point 82 means that an amount of moisture corresponding to the ordinate distance between the
Points 74 and 82 corresponds to where 60 becomes steam rich. Since the small auxiliary air flow has been taken over from outside air in the atmosphere. stands, he receives a starting point according to point Von that formed by the flow path 42, 48 96 in FIG. 6, an outlet line 83 branches off from the circuit below the primary air, through which it separates and, for example, a relative humidity which escapes a part of the steam-rich atmosphere with a moisture content of 50% and a temperature of the level according to point 82, which corresponds to the amount of 65 35 ⁰ C can correspond. The moisture level of the auxiliary air flow supplied to the circuit from the auxiliary air flow after the double passage corresponds to flow path 72. It goes without saying that through the rotor is represented by the line 98 of FIG. 6 that reproduced here as well as in the other execution. This moisture level is allowed because

Condition brought according to the moisture level according to line 84, which is a part of the rotor mass removing moisture.

In the embodiment according to FIGS. 5 and 6, the small auxiliary air flow, which has the task of To remove moisture from the mass of the rotor 12 or to cool the mass after the passage through the steam-rich zone twice

agreement with Fig. 3 in the flow path 42, 48 formed circulation circle are initiated.

The steam-rich atmosphere in this circulation cycle experiences essentially the same changes in state as in the embodiment according to FIGS. 1 and 2. It is also assumed that the Primary air dehumidified in the same way as before

the air flow is better utilized than is assumed to be higher than in the exemplary embodiments described above.

The F i g. 7 shows an embodiment which differs from the previous one in that the auxiliary air flow is also circulated in a closed flow circuit. The fan 86 guides the auxiliary air flow in the flow branch 38 upwards between the intermediate walls 68 and 88 located below the rotor through the mass of the rotor to the sector 99 located above the rotor between the intermediate walls 24 and 28. At the transition between the dehumidification zone in sector 32 and the steam circulation zone in Sector 40, smaller sectors 100, 102 are also arranged on the side opposite sector 99, which sectors are delimited in the upper housing part by partition walls 26 and 104 and in the lower housing part by partition walls 22 and 106. The small auxiliary air flow passes in the upper part of the apparatus into the upper _a o sector 100, from there downwards through the rotor in the flow path 108 to the lower sector 102 and back to the fan 86.

The rotor 12 is driven by the upward branch of the auxiliary air flow according to flow path 38 cooled and preheated by the downward branch in the flow channel 108. The cooling takes place through the transfer of sensible heat to the air flow or the evaporation of moisture from the Rotor in the air stream. Preheating also takes place by transferring sensible heat, but in the opposite direction and through condensation of moisture in the rotor. The steam content in the auxiliary air flow becomes high and would, if no leakage losses occur and he with im Air located in the rotor would be diluted, especially in the downward branch in the Flow path 108 can reach atmospheric pressure.

In addition, the course in the steam circulation system, as can also be seen from the diagram in Fig. 8, the same as in the embodiment of FIG. 1. Since the example of FIG Regeneration side has only closed circulation circles, a tapping of steam from the must through the circulation system formed by the flow path 42, 48 take place, which is made possible by the outlet 83 will.

A small auxiliary air flow can be drawn directly from the outside air into the circulation circuit (flow path 42, 48) are mixed in, especially in the example according to FIG. 7, as indicated by the dash-dotted line Inlet 110 is indicated, which can be attached to the suction side of the fan 44 and then of course is provided with a throttle.

During a start-up period in which the circulation circuit in the various exemplary embodiments is on Contains atmospheric air at the beginning, this gradually increases its vapor content by absorbing moisture evaporated from the mass of the rotor until the permanent state described above is reached has been.

The invention is of course not limited to the exemplary embodiments shown, but rather in the in the broadest sense within the framework of the underlying inventive concept. The housing 10 can thus rotate, while the moisture-absorbing mass does not rotate is. Both the housing and the transmission body can also be stationary.

Claims (16)

Patent claims: 1. Method for regenerating a moisture exchanger for air conditioning systems with a in a housing encircling transfer body, the flow channels having Mass successively with an air flow (primary flow), from which the mass absorbs moisture, and with a regeneration stream, with the help of which and by the supply of heat from a heating device, the one received in this way Steam is removed from the mass, is brought into contact, characterized in that that this heat supply to the mass (16, 18) by a gas flow, for example air flow, guided through the channels, takes place, which circulates in a circuit (42, 48) between the mass and the heating device (46) becomes such that it is essential both before and after passage through the mass has a higher steam content than the primary stream (36), but with the absolute pressure of the gas flow, for example air flow, is lower than that of the primary flow during the Passage through the respective zone. 2. The method according to claim 1, characterized in that in addition to the circulated vapor-rich gas flow, for example air flow, in relation to the primary flow (36) small auxiliary air stream (38, 72) for flowing through the channels of the mass to the side of the Zone (32) of the primary flow is brought. 3. The method according to claim 2, characterized in that the auxiliary air flow (38, 72) when entering the ducts has a lower temperature than the circulated steam-rich gas stream, for example airflow. 4. The method according to claim 2 or 3, characterized in that the auxiliary air flow (38, 72) has a lower vapor content than the circulating vapor-rich gas stream, for example Airflow. 5. The method according to claim 1 to 4, characterized in that the auxiliary air flow (38, Fig. 1; 72, Fig. 3) the primary stream (36) either is removed before or after its passage through the mass. 6. The method according to any one of the preceding claims, characterized in that the small auxiliary air stream (38, 72) to flow through a zone of the transmission body (12) is brought, which is moved to the side of the circulation zone (40), where the treatment of the mass by the steam-rich gas flow, for example air flow, is ended, the auxiliary air flow the mass cools and also absorbs moisture from it. 7. The method according to claim 6, characterized in that the auxiliary air stream (72, F i g. 3) after its passage through the mass in the circulation circle (42, 48) introduced and with the in this located vapor-rich gas stream, for example air stream, is mixed, which thereby is enabled to remove moisture from the mass itself. «9 657/119 8. The method according to claim 6 or 7, characterized in that the auxiliary air flow (38, F i g. 5 and 7) is made to successively two or more next to the circulation zone (40) to flow through designated zones. 9. The method according to claim 8, characterized in that the auxiliary air stream (38, F i g. 5) is made to flow through two zones, one after the other, next to the circulation zone (40) are provided on the side where the treatment of the mass by the steam-rich Gas flow, for example air flow, has ended. 10. The method according to claim 9, characterized in that the auxiliary air stream (38, F i g. 5) is made to flow through the zone closest to the circulation zone (40) last. 11. The method according to claim 8, characterized in that the auxiliary air stream (38, F i g. 7) is brought about in a closed circuit through both sides of the circulation zone (40) designated zones (99, 100) to flow. 12. Moisture exchanger for carrying out the method according to one of the preceding Claims, provided with a housing and a transmission body accommodated in this and comprising a continuous channel Mass with hygroscopic properties, the case and the body being one Perform relative movement to each other on a closed path, while a Air flow containing steam (primary flow) is passed through a zone of the mass and a Regeneration stream heated by a heater through another zone of the mass, thereby characterized in that the regeneration zone (40) and the heating device (46) in a closed Circulation circuit (42, 48) for a means participating in the regeneration that is given an absolute pressure in this zone that is lower than the pressure of the Primary current in its zone (32). 13. Moisture exchanger according to claim 13, characterized by passages for the Passing through a small auxiliary air stream (38, 72) that also takes part in the regeneration by a third zone (34) of the mass, which lies between the two other zones (32, 40). 14. Moisture exchanger according to claim 13, characterized in that the outlet side the third zone through a line (72) with the closed circulation circuit (42, 48) in connection stands. 15. Moisture exchanger according to claim 13, characterized by two or more Zones arranged in series with one another for the small auxiliary air flow (Fig. 5). 16. Moisture exchanger according to claim 13, characterized in that certain zones on both sides for the auxiliary air flow (38) the drying zone (32) and the circulation zone (40) provided and together to form a closed Circle connected (Fig. 7). Considered publications:
U.S. Patent Nos. 2,053,159, 2,136,513,
547. For this purpose 2 sheets of drawings 409 657/119 8.64 © Bundesdruckerei Berlin